Comment 3 for bug 1096053

Upstream webkit has AArch64 support now due to Apple A7 cpu used in iPhone 5S and some iPads.

But building for aarch64-gnu-linux fails due to __arm64__ != __aarch64__ definitions. After changing WTF/wtf/Platform.h to make use of __aarch64__ to set WTF_CPU_ARM64 it fails in lot of places:

/tmp/cckuPd0e.s:16393: Error: the optional immediate offset can only be 0 at operand 3 -- `stxr w3,w2,[x0,1048]'
/tmp/cckuPd0e.s:16574: Error: the optional immediate offset can only be 0 at operand 2 -- `ldxr w1,[x19,1048]'
/tmp/cckuPd0e.s:16577: Error: the optional immediate offset can only be 0 at operand 3 -- `stxr w0,w20,[x19,1048]'

I suspect LLVM/CLang != GCC stuff here.